Cellular Respiration Energy Connection Energy Transformation in Living Organisms- Cell Process Cellular Respiration Energy Connection

Review: Producers Producers get their energy from the sun. Producers convert this light energy into stored chemical energy (glucose). This process is called photosynthesis.

Review: Consumers Consumers get their energy from the producers. Consumers convert stored chemical energy (glucose) into usable chemical energy (ATP). This process is called cellular respiration.

Why Do Cells Need Energy? Cells Need Energy To: move change shape repair structure make new cell parts transport food expel wastes

The Cells Fuel: ATP Adenosine triphosphate = ATP Major fuel used for all cell activities Food molecules (carbs or fats) are broken down – released energy is ATP

Food Eaten Release Energy Energy is stored in carbohydrates and lipids Energy release is ATP Energy (ATP) is used by the Cells to perform cell activities

D. Cellular Respiration (Process) a. Process that cells break down simple food molecules and release energy After you eat, your body converts carbohydrates (sugars and starches) into ATP When the body needs energy (ATP), cells “withdraw” energy (ATP) from glucose b. Occurs in both plants and animals Occurs in the mitochondria You breathe for your mitochondria

Cellular Respiration c. Converts the food we eat into energy for the cell d. Lots of the energy is stored in the form of ATP (fuel for the cell) e. Most of the energy is released in the form of heat… which helps to maintain a constant body temperature e. Produces carbon dioxide gas

REACTANTS PRODUCTS

E. Cellular Respiration Chemical Equation Raw Materials Products C6H1206 + 602 6C02 + 6H20 + Energy Glucose Oxygen Carbon Dioxide Water ATP

F. Comparison of the 2 Cell Processes Cellular Respiration Photosynthesis

Photosynthesis and Cellular Respiration *They are opposites!* They both provide energy. * They form a cycle!

Photosynthesis and Cellular Respiration Working Together

Do only animals respire? Or do plants respire too? The BIG Question is… Do only animals respire? Or do plants respire too? Only plants perform photosynthesis Plants AND animals perform cellular respiration! (Can you explain why??)

Site of Cellular Respiration Both plant and animal cells contain mitochondria: cell structures that transform chemical energy from glucose to ATP.

Significant ATP Production Aerobic (with oxygen) cellular respiration releases energy SLOWLY, using oxygen to convert ONE molecule of glucose to 36 ATP!

Cellular Respiration (anaerobic) (Without oxygen) What happens when cells don’t have enough oxygen? Some organisms live in an oxygen-free environment. How do they get their energy?

Cellular Respiration (anaerobic) Anaerobic respiration is also called fermentation, or the process by which energy is released from glucose when oxygen is NOT available. This process allows organisms to continue to produce energy until oxygen is available. However, this process only releases 2 ATP per molecule of glucose.

Alcoholic Fermentation Anaerobic way of converting energy for yeast and other microorganisms Glucose broken down to produce alcohol, CO2 and energy (ATP) C6H12O6  ethanol + CO2 + 2 ATP EX: baking bread with yeast fermenting wine & beer

Fermentation - Bread Source of sugar? DOUGH! (sugar and/or flour) Yeast use up the O2 and ferment sugar Produce CO2, which is trapped within tiny bubbles & results in the dough rising Produce ethanol, which evaporates in the baking process Yeast Cells Dough Fermenting

Fermentation - Wine Source of sugar? GRAPES! Yeast use up the O2 and ferment sugar Produce CO2 (kept only in champagne) Produce ethanol (% alcohol varies based on sugar content of grapes and # of fermentations)

Fermentation - Beer Source of sugar? BARLEY! Yeast use up the O2 and ferment sugar Hops are added as a preservative and for added flavor Produce CO2 and ethanol also Various carbohydrates can be used to make alcohol – including wheat, rice, and potatoes!

Lactic Acid Fermentation Anaerobic way of converting energy in animal cells and some microorganisms Glucose broken down to produce lactic acid, CO2 and energy (ATP) C6H12O6  lactic acid + CO2 + 2 ATP EX: muscle cells during strenuous exercise, fermenting cheese, yogurt, sour cream

Strenuous Exercise Lactic acid is produced by your muscle cells during rapid exercise when the body cannot supply enough O2 to tissues. Without enough O2, the body is NOT able to produce all of the ATP that is required. The buildup of lactic acid can cause painful burning in your muscles!

Minimal ATP Production In the absence of oxygen, anaerobic respiration only releases 2 ATP for each molecule of glucose broken down.

Comparing ATP Production First, your body breaks down glucose through aerobic respiration to produce 36 ATP per glucose molecule; however, this is a slow process. When muscle cells cannot get enough O2 they break down glucose through lactic acid fermentation to produce 2 ATP per glucose… Therefore, AEROBIC RESPIRATION is much more efficient in terms of ATP production – 36 ATP compared to 2 ATP!

Aerobic Training Ex: long runs, biking, swimming Can increase the size and number of mitochondria in muscle cells Can increase the delivery of O2 to muscles by improving the heart and lungs

Anaerobic Training Ex: sprints, strides, quick bursts of energy Increase the glycogen levels in the muscles Increase body’s tolerance to lactic acid